1. Field of the Invention
The apparatus of the present invention relates to temperature responsive control devices. More particularly, the apparatus of the present invention relates to a system in connection with a gas pressure regulator device utilized for controlling the supply of gas from a pumping utility system to a designated area within that system, the control device responsive to changes in weather temperature for controlling the gas pressure within the system.
2. General Background
It is well known in the supply of gas from a public utility system, that the need for gas is directly related to any change in temperature, when a great deal of the gas from the system is utilized for heating homes and the like. Therefore, when a specific district or region which is supplied by a public utility system undergoes a change in weather temperature, for example, when the weather becomes very cold, the demand for gas is increased, and therefore, it is requisitely necessary that the gas pressure within the system be also increased in order to meet this demand. In the present state of the art, it is very common that in attempting to anticipate cold weather approaching a particular district or region, that the regulators which regulate the supply of gas to a certain region, be manually adjusted so that the pressure in the regulator is increased to meet this demand.
Likewise, when warm weather is approaching it is unnecessary to have a high pressure on the system, since this pressure is not needed due to the reduced use of gas in the system; therefore, the regulators again must be manually adjusted so as to effect a reduced pressure supply in the system. Often times, this is a time consuming use of man power in that each regulator must be manually attended throughout the region which may include a number of regulators in order to properly adjust the system, which, of course would lead to a greater possibility of human error being involved in the adjustments which would not necessarily coincide with the pressure needed within the system. Likewise, if the cold weather were to be unanticipated it would be a possibility that the pressure which is in the system could not be adjusted in time, and therefore the loss of pressure within the system could severely affect the supply of gas to be used and could possibly cause an interruption in the flow of gas which would of course endanger the lives of the users were the gas to return into the system.
The type of regulators which are utilized are the type of which are provided with a diaphragm which is controlled in one form of device by means of a weight or like attached to the end of a lever arm for exerting pressure against the diaphragm in opposition to the pressure exerted by the gas supply. In this particular type of regulator, it is common for the utility employees, or the case of the so-called "bottled gas" it is a practice for the service men who deliver the service supplies of gas to make the appropraite changes in the regulator by adding or reducing weight from the lever in accordance with the expected temperatures.
In another form of regulator, a spring system is utilized to control the diaphragm of the regulator but in this case also the regulator will supply gas only at a certain pressure once the spring pressures have been adjusted. The disadvantage of both of these conventional regulators is that, particularly in isolated locations, there is no way in which the adjustment of the regulator may be changed by those unfamilar with the mechanism in response to sudden or unusual changes in weather conditions. Thus, in the winter months it may occur frequently that the gas pressure supply is insufficient to provide proper heating for a building in which the furnace is fired by gas.
There have been several patents issued which relate to regulators and their use in gas supply systems, the most pertinent being as follows:
U.S. Pat. Nos. 2,404,596 issued to Rouche; 3,155,317 issued to Puster; and 3,181,789 issued to Fall, all disclose a combination of a fluid expansable bulb that is temperature responsive and causes a fluid to apply pressure to bellows which through various linkage moves the control valve.
U.S. Pat. Nos. 2,182,873 and 2,309,848 both teach the type of a Fisher-King Valve responding indirectly to temperature and uses gas in the line itself through an orifice to apply pressure to the diaphragm and a pilot relay to feed such pressure to the diaphragm.